Solar Growing?

Staff

02/01/2006

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Proponents of solar power won a recent victory in the campaign for photovoltaics when national retailer Walgreens recently announced it will install PV systems on 96 stores and two distribution centers in California and 16 stores in New Jersey. The new systems will generate more than 13.8 million kilowatt-hours per year, making this the largest solar project ever completed in the United States. The first systems are expected to be operational in early 2006. Solar roof tiles will enable each facility to generate between 20% and 50% of its own electricity on site.

At the AHR expo in Chicago last month, PV roof provider Solar Integrated Technologies, Inc., Los Angeles, also conducted a news conference announcing that it completed 39 industrial solar roofing projects in 2005, bringing its total installed projects to 58, aggregating more than 5 MW of installed generating capacity.

Tim Kehrli, the company's director of government sales, admits most of this work is in the Southwest, notably California, but they're also seeing more work out East. "We go where the money," said Kehrli. "And right now, New Jersey is where the incentives are."

New York is also a hot bed of activity out East, and across the pond, they've done a lot of work in Germany, frankly because that country has an electricity payback program, he said.

Still, Kehrli believed there is a $100-billion per year market out there to be realized—and a lot of that just involves retrofitting all the flat roof of big-box facilities. The company's base of customers includes Coca Cola, Frito Lay, the Air Force and the San Diego school system, which is having its schools retrofitted with the thin, flexible roof system. And because their product is a roofing system, complete with power and insulation, Kehrli said, it really is a two-for-one deal and the company guarantees the system for 20 years.

He predicts the government will become their next big client. "With the new mandate that all federal buildings only consume a set amount of energy per year, renewable resources are going to become very viable technologies."

Still, not everyone at AHR was as high on solar. During an ASHRAE-sponsored panel discussion of best practices in tall buildings, Peter Ruggiero, a partner with architect Skidmore Owings and Merrill, Chicago, said that the investment for photovoltaics is just not there.

This statement was certainly in agreement with one made earlier in the session, when Dan Jenkins from Chicago developer John Buck Co. said tenants are not interested in being sold on energy efficiency, because they see it as such a small part of their overall costs. And for developers to justify adding green elements like PV, they must see a clear path for charging tenants more for these amenities. That said, he added the green building movement is gaining critical mass, but that the economics of programs like LEED must be better communicated, and that governmental bodies need to step up with incentives to get developers on the bandwagon.

Ruggiero, however, reported more unorthodox green measures are making their way into buildings. On their World Trade Center 7 project in Manhattan, SOM is going with an unheard of amount of clear glass. "At some point, the architectural community decided sunlight was 'bad' and needed to be reflected away. Fortunately, things have come full circle," he said.

Reg Monteyne, a senior vice president with the San Francisco office of consulting engineer Flack + Kurtz, agreed whole-heartedly that daylighting is definitely affecting tall building design. But with these schemes, designers need to consider intelligent and automated shading and dimming strategies. Another project in Manhattan that his firm is involved with, the new New York Times headquarters, also involves extensive glass and natural lighting. But to deal with all the extra light, a custom, smart shading system had to be designed.

"There still has to be a balance point between view and natural light vs. glare and unwanted heat gain," said Monteyne.

Ruggiero is also experimenting with other forms of renewable energy. In one high-rise SOM he is doing in China, they're taking an architectural feature and turning it into a power generation/building stabilization element. In a nutshell, the building includes a funneled aperture toward the top of the structure that helps against sway effect. At the same time, Ruggiero said, they're using the wind that blows through this opening to power wind generators that will help power the building itself.

Monteyne said F+K is also experimenting with the wind in China, not for power generation, but better IAQ. On the Jinao Tower in Nanjing, they're working with a ventilated facade that's essentially a double envelope that literally brings in air from one side of the building and vents it on the other.

Enhanced building facades are important, according to Monteyne, as they're a vehicle that can help building teams meet the requirements of ASHRAE 62. He's also seeing underfloor air systems become more common as the result of the new ventilation standard, but more importantly, he noted they're beginning to observe a harmonious divorce between ventilation and air supply and space conditioning itself, which may prove a very important change for building HVAC design. Of course, he concedes, UFAD and ventilated facades work best in climates with a mild-year-round climate.

Wind power is also picking up in the Windy City, the host of this year's AHR Expo. According to a recent report from the Chicago Sun Times, the city will mount two wind turbines on top of Daley Center, and eight more on a Helmut Jahn-designed building on the Near North Side.